The present invention relates to a display system for indicating at least two kinds of data on different portions of the face of an indicator respectively, or on the whole display surface of an indicator at different times respectively, and for mutually associating the two kinds of data with each other. The two kinds of data are written into different memory units successively and respectively to be stored. Each kind of data is selectively displayed on the whole surface of an indicator when only one kind of data is read out at a time from a corresponding memory unit. The two kinds of data are respectively displayed on two corresponding portions of an indicator by dividing the whole surface of the indicator into two parts, when the two kinds of data are simultaneously read out from the memory units to the indicator. The two resultant displayed pictures are associated with each other by means of recognizable marks assigned to the one or two pictures.
The present invention will be described below as embodied in a ship track and underwater conditions indicating system.
A prior art ship track and underwater conditions indicating system is disclosed in a Japanese patent application publication No. 142484/1986. The prior art system selectively displays the track of a ship or the underwater conditions under the ship's track on the whole screen of an indicator at any instant of time. One of the drawbacks of the prior art system is that a previous point on the ship track shown in one picture can not be associated with the underwater conditions under the same point shown in the other displayed picture.
Another prior art ship track and underwater conditions indicating system is disclosed in a Japanese patent application publication No. 265590/1986. The prior art system displays the track of a ship in the upper part of the screen of an indicator, and indicates the underwater conditions under the ship track in the lower part of thereof. One of the drawbacks of the prior art system is that a previous point on the ship track can not be associated with the underwater conditions under the same point.